Tripping Behavior of Circuit Breakers

In summary: Many 240 volt appliances in US don't use a Neutral wire and are connected as you describe. My water heater is so connected.Many 240 volt appliances in the US don't use a Neutral wire. They are connected as you describe. My water heater is so connected.
  • #36
kiki_danc said:
In other countries.. do your refrigerators really have ground?
yes.
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  • #37
jim hardy said:

If you will read the 8 pages of thread here.. you will understand that we here literally don't use grounds. These discussions were by different people in my country.. it proves what I describe is true.. one of them wrote in page 4:

https://www.philippines-expats.com/topic/29039-grounding-of-electric-appliances/?page=4

"Over the years in Philippines I have had no trouble with shocks from most appliances but there are 3 that always give me trouble. They are cheap electric stovetops, coffee kettles, and submersible water heaters. I have had many shocks from each of these to the point where I don't use any of them if I can help it. "

and someone died from it: here:

"Aah the Philippines wiring !

Just this Tuesday we were told one of the wifes old friends died from an electric shock from a rice cooker !"

So it's worse than you think.
 
  • #38
kiki_danc said:
What they don't know is that even if your stick the hanging wire to earth.. it won't trip the breaker if it's not connected to the centertap of the utility pole or transfomers, right? It may be basic thing to you but most of my country men don't know about it. I only learned it this 2 weeks here.

Well you're getting by.
Progress not perfection ?

Are there any exposed metal parts on your fridge or are all surfaces plastic ?

I cannot in good faith advise you to take shortcuts.
Make your own house right , others will follow .

How frequent are electrocutions over there? That'll drive change........................

Curiosity - what refrigerant do you use over there ?
We still use Freon (R134 , R410 etx) because most varieties aren't very flammable. but it's expensive.
Europe allows Propane(R290) which is flammable but cheap and they're having explosions when it leaks .
To each his own
............................
Well i just learned US got on the Propane bandwagon last year. I hope they approve it for cars - it works great !
https://www.epa.gov/sites/production/files/2018-08/documents/epa_frdoc_0001-22694.pdf

old jim
 
  • #39
jim hardy said:
Well you're getting by.
Progress not perfection ?

Are there any exposed metal parts on your fridge or are all surfaces plastic ?

I'm not sure but magnets can easily stick to the surface of ref.. how can I tell if it's metallic surface? If I'll put a multimeter to measure continuity, the paint may block it.

If the power utilities won't put wires from their centertap to my ground in my home.. then I guess I'll spray all my metallic appliance with thick plastic paint? What kind can do this? Btw... in our neighborhood.. we have one transformer for every street with say 10 houses... the power utility would waste a lot of wires if they would tap the centertap to each house. In your country, the centertap goes to every dozen houses for one transformer?

Btw.. my office building is connected to the centertap because they made me buy the 3 phase open delta pole transformers for $4000 (because others were already used up). Since the transformers are partly mine, they have no trouble sharing a wire from centertap to my service entrance. But for other owners who don't own the transformers.. utilities are saving wires by not tapping the centertap to the service entrances of residences.

Btw.. in the 3 phase open delta.. one of the wires when tested against ground is 210 volts.. while the other 2 of the 3 phase is 120 volts.. Open Delta really do this? When the 210volts line is tested against one of the 2 other.. it is back to 120 volts.. what kind of phase manipulation can do this?
I cannot in good faith advise you to take shortcuts.
Make your own house right , others will follow .

How frequent are electrocutions over there? That'll drive change........................

Curiosity - what refrigerant do you use over there ?
We still use Freon (R134 , R410 etx) because most varieties aren't very flammable. but it's expensive.
Europe allows Propane(R290) which is flammable but cheap and they're having explosions when it leaks .
To each his own
............................
Well i just learned US got on the Propane bandwagon last year. I hope they approve it for cars - it works great !
https://www.epa.gov/sites/production/files/2018-08/documents/epa_frdoc_0001-22694.pdf

old jim

I'm not sure what refrigerant, i'll check.
 
  • #40
Some electrical engineers in my country are confused too. For example the following post is from an electrical engineer (He was confused about floating ground.. what is your comment about the floating ground?)

http://www.pinoyhandyman.com/forum/in-and-out-of-the-house/home-building-and-improvement/63-meralco-s-3-wire-service-entrace

"
Meralco's 3-wire service entrace
06-28-2007, 03:53 PM

Actually this is the continuation of a comment to an article here. My original comment was: http://www.pinoyhandyman.com/forum/in-and-out-of-the-house/home-building-and-improvement/63-meralco-s-3-wire-service-entrace (note Meralco is name of our major power distribution company)

"This is good news if what Meralco provides is a true ground circuit for the user. The 3rd wire could just be a lighting arrestor to protect Meralco's own investment with no real connection to the transformer's neutral. I'll open a topic in the forum ... this is too long.

Let me continue:

I'm an electrical engineer though I slept through a lot of my power subjects so I'm looking for answers also. My understanding is that to have a ground wire there actually have to be 4-wires from the secondary of the transformer on the post. Why there are 4 is a long story (3 phase/single phase) but suffice it to say that 3 will need to go to your house, two of which are the normal ones and the third is the ground wire. If someone wants the explanation, ask and I do my best, no as-is-where-is though.

It is hard to believe that Meralco is providing a true ground wire because not only is the 4th wire an additional expense but also the transformers used would have to be the more expensive Y-transformers. The normal transformer used is the less expensive delta-transformer. While you can get a "ground" with delta transformers, it is not a true ground with an actual physical point ("node" for the geeks) but rather is a "floating" ground. A floating ground is normally established by driving a long copper rod into the earth, you can sometimes see these beside electrical posts with a big wire from it running up the post. While "floating" grounds are ok for lightning protection, I have my doubts about Earth leakage current (the stuff that shocks us when an appliance is "grounded").

So I am wondering if this really a true ground."

Another person reply in the site which summarized what I was describing that centertap was not wired to most of our country house was :

"Notice however that these transformers near our house only have two wires coming to them. These two wires are two of the three at the high voltage 3 phase transformer, the neutral is not distributed. Rather I believe standard practice is to connect the neutral to an Earth ground. The soil is used to "distribute" it."

Exception is if you buy the transfomers or during Christmas when they get more generous from bonuses.. they tap the centertap to your house.. but usually it's not done for majority.
 
  • #41
kiki_danc said:
Btw.. in the 3 phase open delta.. one of the wires when tested against ground is 210 volts.. while the other 2 of the 3 phase is 120 volts.. Open Delta really do this? When the 210volts line is tested against one of the 2 other.. it is back to 120 volts.. what kind of phase manipulation can do this?

Look up 'high leg delta"
equilateral triangle 240 volts per side
by geometry distance from from L3 to N(more precisely to center of base) is √(2402 -1202) = 207
and that's what you ought to read.
That you measure just 210 suggests to me that there's not anything really unexpected there.

233px-High_leg_delta_transformer.svg.png

Open delta just omits one of the transformers
(and that used to be a common delivery scheme in US but they're discouraging it in Colorado and some other states.)
so the triangle can distort if the transformers are electrically less than 'rigid'
kiki_danc said:
When the 210volts line is tested against one of the 2 other.. it is back to 120 volts.. what kind of phase manipulation can do this?
Get an architect's scale and drawing compass
construct yourself a triangle to scale with sides in proportion to your measured voltages
base L1-L2 = 240 (or whatever you measure) units long
""210 volts line is tested against one of the 2 other.. it is back to 120 volts.""
tells me L1-L3 and L2-:L3 are both 120
and L3-Gnd is 210Can you draw a triangle that meets those constraints?
Kirchoff's voltage law says the voltages MUST form a closed geometric shape , and with just three terminals it has to be a triangle but not necessarily equilateral.
Voltage between ground and Neutral terminal in middle of bottom transformer is unknown .
You should be able to find it from voltage measurements and graphics.

Make careful measurements and double check them for it's tedious redrawing the triangles
You might find there's voltage between N and Ground . Especially if there's no wire on N..
Or you might find the triangle isn't quite equilateral and L3 isn't right above N.

Anyhow that's an exercise you should undertake to deepen your understanding.

Keep up the good work and you'll become the " Go To Guy " fpr electrical
but keep in mind - "The biggest part of being smart is being aware of how little we know."
Mother Nature reminds me of that frequently.

old jim
 

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  • #42
kiki_danc said:
I have had many shocks from each of these to the point where I don't use any of them if I can help it. "

and someone died from it: here:

"Aah the Philippines wiring !

Just this Tuesday we were told one of the wifes old friends died from an electric shock from a rice cooker !"

So it's worse than you think.

If that's the case, then the time is ripe in Philippines for a Ralph Nader type to start a movement.
"Electric companies are killing people !"

I'm surprised some politician has not already lept onto the matter.

A responsible newspaper reporter who understood the subject matter could write a compelling series of articles to raise public awareness.

"When the student is ready a teacher will appear".
Might be you're going to be that teacher.

GFCI outlets would save lives. But the ones I'm familar with need a ground connection.
 
  • #43
It seems that this thread is drifting into politics. The OP'S original question is answered.

Thread closed.
 
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